Release-mode plugin builds link against Debug libraries #552

D:\develop\OSVR-Core\examples\plugin\selfcontained>mkdir build
D:\develop\OSVR-Core\examples\plugin\selfcontained>cd build
D:\develop\OSVR-Core\examples\plugin\selfcontained\build>cmake -G "Visual Studio 14 2015 Win64" ..
-- The C compiler identification is MSVC 19.0.24215.1
-- The CXX compiler identification is MSVC 19.0.24215.1
-- Check for working C compiler: C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/bin/x86_amd64/cl.exe
-- Check for working C compiler: C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/bin/x86_amd64/cl.exe -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working CXX compiler: C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/bin/x86_amd64/cl.exe
-- Check for working CXX compiler: C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/bin/x86_amd64/cl.exe -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info 
- done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: D:/develop/OSVR-Core/examples/plugin/selfcontained/build`

1>------ Build started: Project: ZERO_CHECK, Configuration: Release x64 ------
1>  Checking Build System
1>  CMake does not need to re-run because D:/develop/OSVR-Core/examples/plugin/selfcontained/build/CMakeFiles/generate.stamp is up-to-date.
2>------ Build started: Project: com_osvr_example_selfcontained, Configuration: Release x64 ------
2>  Building Custom Rule D:/develop/OSVR-Core/examples/plugin/selfcontained/CMakeLists.txt
2>  CMake does not need to re-run because D:/develop/OSVR-Core/examples/plugin/selfcontained/build/CMakeFiles/generate.stamp is up-to-date.
2>  [osvr_convert_json] Generating string literal header from com_osvr_example_selfcontained.json
2>  com_osvr_example_selfcontained.cpp
2>     Creating library D:/develop/OSVR-Core/examples/plugin/selfcontained/build/Release/com_osvr_example_selfcontained.lib and object D:/develop/OSVR-Core/examples/plugin/selfcontained/build/Release/com_osvr_example_selfcontained.exp
2>  com_osvr_example_selfcontained.vcxproj -> D:\develop\OSVR-Core\examples\plugin\selfcontained\build\bin\osvr-plugins-0\Release\com_osvr_example_selfcontained.dll
3>------ Build started: Project: ALL_BUILD, Configuration: Release x64 ------
3>  Building Custom Rule D:/develop/OSVR-Core/examples/plugin/selfcontained/CMakeLists.txt
3>  CMake does not need to re-run because D:/develop/OSVR-Core/examples/plugin/selfcontained/build/CMakeFiles/generate.stamp is up-to-date.
========== Build: 3 succeeded, 0 failed, 0 up-to-date, 0 skipped ==========

June 23 08:44:29.382 info [OSVR]: Logging for C:\Program Files\OSVR\Runtime\bin\osvr_server.exe
June 23 08:44:29.382 info [OSVR Server]: Using default config file - pass a filename on the command line to use a different one.
June 23 08:44:29.382 info [OSVR Server]: Attempting to load config file 'osvr_server_config.json'.
June 23 08:44:29.382 info [OSVR Server]: Constructing server as configured...
June 23 08:44:29.397 info [OSVR Server]: Loading auto-loadable plugins...
June 23 08:44:29.413 warning [PluginHost]: Failed to load plugin com_osvr_example_selfcontained: Failed to load the module C:/Program Files/OSVR/Runtime/bin/osvr-plugins-0/com_osvr_example_selfcontained
June 23 08:44:29.429 info [OSVR Server]: Loading plugins...
June 23 08:44:29.429 info [OSVR Server]: Instantiating configured drivers...